Anti-war campaigners are pledging ongoing civil disobedience after a man was arrested for trespass during a protest at the Defence headquarters near Canberra.

Bryan Law, 57, from Cairns was among 10 members of the group Faith Based Peace Witnesses protesting against the special forces deployment in Afghanistan.

New South Wales police say Law was arrested and remains in custody in Queanbeyan while investigations continue.

Protest organiser Adrian Glamorgan says the group approached the gates of the Defence Headquarters Joint Operations Command Centre south of Bungendore this morning and read a notice calling for Australia to quit the war in Afghanistan.

"The people of Australia have been democratically ignored for too long about their wish to find peaceful solutions to Afghanistan," he said.

He says the group is planning further action until special forces are withdrawn from Afghanistan.

"Civil disobedience accepts the fact that at some point you might end up in jail and that is something we willingly accept. That is a sacrifice," he said.

"But right now the people of Afghanistan are being sacrificed. The women and the children and people with disabilities are having resources denied because of the non-ending war in Afghanistan."